Information-Theoretic Description of No-go Theorem of a Bit Commitment

Yoshihiro Nambu; Yoshie Chiba-Kohno

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Information-Theoretic Description of No-go Theorem of a Bit Commitment

Yoshihiro Nambu·Yoshie Chiba-Kohno

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Abstract

We give a comprehensive and constructive proof of the no-go theorem of a bit commitment given by Mayers, Lo, and Chau from the viewpoint of quantum information theory. It is shown that there is a trade-off relation between information acquired by Bob during the commitment phase and the ability to change a commit bit by Alice during the opening phase. It is clarified that a protocol that is unbiased to both Alice and Bob cannot be, at the same time, secure against both parties. Fundamental physical constraints that govern this no-go theorem are also discussed.

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Yoshihiro Nambu, Yoshie Chiba-Kohno. 2000-11-21. Information-Theoretic Description of No-go Theorem of a Bit Commitment. https://arxiv.org/abs/quant-ph/0011068

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